1. When and by Whom Was the Judo Black Belt Created?
Judo was founded by the educator Jigoro Kano. In 1882, he rented a room at a temple called Eisho-ji in Tokyo to open a dojo called Kodokan [1]. Kano introduced a ranking system based on the board games Go and Shogi [4]. The first shodan ranks were awarded about one year after the dojo opened, in August 1883. Two disciples, Tsunejiro Tomita and Shiro Saigo, received the first shodan ranks at Kodokan [3].
When ranked practitioners began wearing black belts varies in historical records. Wikipedia states that the practice began when outstanding talent emerged among the students, leading to black belts being assigned to those with ranks [2]. The International Judo Federation (IJF) notes that illustrations confirming the existence of the belt system date back to 1886, but the first written mention of belts is from 1913 [20].
This raises a curious question: where did the concept of "dan" ranks actually come from? It did not originate from sword techniques. Kano found his inspiration in a completely different kind of game.
2. Why Jigoro Kano Borrowed the "Dan" Ranks from Go and Shogi
When Jigoro Kano conceived the dan ranking system, he did not look to swordsmanship for reference. Instead, he looked to Go and Shogi, which are board games [4]. These games had a system for showing skill using "dan" numbers long before Judo existed. The "dan" in Judo was born by adopting this existing mechanism.
It is a surprising fact that the roots of words used to describe strength in combat sports lie in quiet board games.
3. How Go Ranks Began Over 200 Years Before Judo
Go ranks existed nearly 200 years before Judo. In the late 17th century, Honinbo Dosaku (1645–1702) set up a framework in which Meijin ranked as ninth dan, Jun-Meijin as eighth dan, and Jozu as seventh dan, with each two-dan difference representing the strength of one stone [5].
Dosaku was so strong that he defeated top players one after another and was praised as having the "strength of thirteenth-dan." However, the official upper limit for Go ranks was ninth-dan. His actual strength exceeded the rank system, but no rank existed to represent it [6].
4. How Shogi Ranks Began with the 1717 List of Players
Shogi ranks also existed long before Judo. In 1717, the first list of ranked players, called "Shogi Zuikokan," was created [7]. This list contained 167 people. The breakdown was 3 seventh-dans, 1 sixth-dan, 4 fifth-dans, 17 fourth-dans, 32 third-dans, 20 second-dans, and 90 first-dans [8]. The largest group was the first-dan group, which made up more than half of the total (about 54%). It formed a wide pyramid shape where the number of players decreased as the rank went up.
Before this list was made, Shogi did not use "dan" numbers at all. Instead, licenses used a system that noted the handicap difference compared to a "Meijin" (master) [9].
5. How Judo's Colored Belts Travelled from Japan to France
In modern Judo, belt colors show rank, from white and brown belts to black, red-and-white, and red belts. Colored belts were actually used in Japan first. The Dai Nippon Butoku Kai, an organization for martial arts, introduced them in its Jujutsu division in 1906. By 1914, Kodokan also used them for youth Judo [10].
Later, in 1935, Mikinosuke Kawaishi, who was teaching Judo at a club in Paris (and later became a seventh-dan at Kodokan), created his own system dividing belts into seven colors: white, yellow, orange, green, blue, brown, and black [11]. It is said that Kawaishi separated the colors because bringing the Japanese system, which had only white and black belts, to other countries made progress hard to see, especially for children who needed clear goals for moving up [12]. The idea of the black belt, born in Japan, developed into a color-coded system abroad and spread around the world.
6. How the "Dan" System Spread to Karate, Kendo, and Kyudo
The "dan" system born in Judo spread to other martial arts. The dan and kyu system in Karate was introduced by referencing Kodokan Judo. The first dan in Karate history is said to have been issued by Gichin Funakoshi in 1924 (Taisho 13) [13]. This was 42 years after Judo was founded.
The dan systems for Kendo and Kyudo were introduced separately from the Judo system by the same organization, the Dai Nippon Butoku Kai, during the Taisho era. While Kendo practice itself has a long history dating back to the Edo period, the addition of "dan" counting came much later [14].
It is important to separate the history of safety equipment, such as bamboo swords and protective gear, from the history of the "dan" counting system. They developed on different timelines.
7. How Belt Colors Change as You Move Up in Judo Rank
In current Judo, the belt color changes as you rise: white belt (4th kyu and below), brown belt (1st to 3rd kyu), and black belt (1st to 5th dan). Above black belt, there are less known colors: red-and-white belts (6th to 8th dan) and red belts (9th and 10th dan) [15].
Promotion exams do not look only at technical skill. Understanding of Judo and contributions to its promotion are also considered. If a person behaves in a way that contradicts the principles of Judo, promotion may not be granted [16]. The exam method differs by rank. For 1st to 6th dan, pass or fail is decided by practical tests. Candidates for 7th dan are evaluated on a five-level scale: "Excellent," "Very Good," "Good," "Pass," and "Fail" [17].
According to one tally, in the more than 120-year history of the Kodokan, a little over a dozen people in total have been awarded 10th dan (in 2006, three men were promoted to 10th dan at the same time for the first time) [18]. Just as the Shogi list had the most people at first dan, Judo also has the widest range of people at 1st to 5th dan. While exact statistics by rank are not confirmed, the structure of belt colors suggests that fewer people reach the higher ranks [19].
8. How Can You Look Into Judo Ranks and Their Roots Yourself?
The websites of the All Japan Judo Federation and the Kodokan publish their promotion-exam rules and the belt colors for each rank. If you are curious, read the original text to see what standards are actually written there [16].
It is also interesting to compare the rank tables of Go and Shogi with the Judo table and check whether all of them take the shape of "first dan (or 1st kyu) has the most people, and fewer people at higher ranks." When you look into it, use reliable sources such as official websites.